Generally, the maximum current consumption of a device (such as a CPU) is determined by the worse case workload that the device may handle at any time, sometimes referred to as “power virus”. Without a protection mechanism, this maximum current may negatively impact chip, package, and system power delivery design.
For example, modern CPU and GPU (Graphics Processing Unit) architectures may implement new functional blocks such as vector operation or accelerator hardware that increase the dynamic range of the power/current and allow much higher power and current “power viruses”. This increased “power virus” current may have a severe impact on the design due to a need for higher voltage to compensate for the I*R (where “I” stands for current and “R” stands for resistance) droop which may in turn cause waste of power (i.e., power consumption increases as the voltage guard-bands increase).
There may also be a negative impact on reliability (i.e., the need for higher voltage to compensate for the I*R droop increases voltage levels and reduces device life). Lower turbo frequency may be achieved since the highest operation point (e.g., when all cores in a processor are working) may be determined by the maximum current needed for worse current “power virus”. Further, package and power delivery costs may be increased because additional capacitors and better voltage regulators may be needed to supply the higher current. Additionally, the system power delivery capabilities may need to be increased in other components such as the battery and/or PSU (Power Supply Unit).